javascript 抓取滑鼠位置

document.onmousemove = function (event) {

  var e = event || window.event;

  if(e.pageX || e.pageY)

    return {x:e.pageX, y:e.pageY};

  else

    return {

      x: e.clientX + document.body.scrollLeft - document.body.clientLeft,

      y: e.clientY + document.body.scrollTop - document.body.clientTop

    };

}